8th Class Science Pollution of Air and Water Air Pollution

         Air Pollution

Air pollution is defined as the addition of undesirable materials into the atmosphere either due to human activities which adversely affect the quality of the air and hence life on earth or through natural process like volcano eruptions.

           Causes of Air Pollution

1. Burning of fossil fuels
2. Motor vehicles
3. Thermal power plants
4. Industries
5. Indoor air pollution
6. Human activities
7. Volcano eruptions

Greenhouse Effect: Greenhouse effect may be defined as a phenomenon that makes the earth's atmosphere to trap the heat from the sun and prevent it from escaping into the outer space/ there by warming the earth's surface. Acid Rain: The burning of fossil fuels containing sulphur, nitrogen and carbon produces acidic oxides of these elements. Carbon dioxide, an oxide of carbon, dissolves in water droplets to produce carbonic acid (a weak acid). The oxides of sulphur and nitrogen react with water to form sulphuric acid (H₂SO₄ and nitric acid (HNO₃) respectively. These acids come down to earth with rain water. Carbonic acid is not a major component of acid rain because it is not as soluble in water as the oxides of sulphur and nitrogen..